A few miles to the east of La Jolla Valley is Sycamore Canyon. There's a fire road that runs along the floor of the canyon all the way from the beach up to Satwiwa/Rancho Sierra Vista in Thousand Oaks, and some glorious side-trails that head off it into the back-country. The road is great for a fairly gentle bike ride, and very popular, and there's some great technical trails on the west side of the canyon. The east half is designated wilderness, so there's no biking. Some of my favorite hiking trails go through the wilderness there though, like Old Boney and Chamberlain trails.
There's a big campground right at the south end of the Canyon, just off the PCH. Sycamore Cove is a large paved site, suitable for RVs, and very, very popular! I don't think there's any time of year that it isn't fully booked in advance. It's in a great location for exploring the mountains, but I've been put off by how busy it is. Probably most suitable if you want a family getaway with access to the beach, it has full facilities including showers and a campground host.
Much less used is Danielson campground, about four miles north up the Canyon fire road. It's a group site, so you'll need to have a large group, a dozen or more, to reserve it. Its location is amazing though, you can drive up the fire road to get there, but it's in a small side-valley, in the center of a grove of oaks. There's a central outdoor fireplace and picnic area left over from when the park was a ranch, and it will comfortably hold a couple of hundred people.
Perhaps the best way to check it out is the annual Santa Monica Mountains Trail Days camp-out, where a hundred or so volunteers camp Friday and Saturday nights, do trail maintenance during the day, and are rewarded with a lovely barbecue on Saturday evening, as well as some entertainment from the rangers. The heading photo is from this years barbecue. It's in the last week of April, keep an eye on the Santa Monica Mountains Trails Council site for details.
Funhouse Photo User Count: 681 total, 81 active. Good to see the total still growing, I still need to find time to update the effects, and maybe add news-feed notifications to see if I can boost growth.